You know, I suspect all these cries for "open borders" and 'fair' treatment for those 'just seeking a better life' would dissolve into loud complaints of "trespassing!" if the issue were a tad more personal and immediate.
   If you had a nice house & garden, and some shady trees, while your neighbors on your street had less charming property and too many kids and no real skills at home renovation and gardening....would you feel as generous and welcoming if they started popping over to forage in your garden, sleep on your porch, have picnics under your trees and send their kids to beg for food at your door...and expected YOU to give them medical attention while they are there?
    If no one would help you keep this traffic OFF your lawn, might you be tempted to build a fence?

Is this a totally accurate analogy? No (YOU could move...the USA can't)...but analogies can't be perfect...they can just point out reasoning patterns and similar attitudes.

   Still, I think it CAN be said that your (probable) reluctance to feed and provide a refuge for your neighbors in YOUR yard, just because "your place looks better" does indicate some of the underlying awkwardness of substituting compassion for 'fairness'.

   I see the value of trying to help those less fortunate than myself....but if I am in a lifeboat, and there are others in the water, there IS some limit to how many more I can allow to climb into the boat before the boat is of little use to anyone.

If "open borders" were made the policy, I see no end to the stream of immegrants...until saturation points were reached and this country was little better than any other....and by that time, Canada WOULD begin to have the same set of problems.

One way of expressing the dilemma is: "If one group is to try to help another, they MUST have the freedom and resources to do it in such a way that the 'helper group' is not dragged down in the process".

(Why do I have these images of old ladies discovered in smelly houses with 147 cats, dead & alive, scattered about?)

Are my dire predictions off the wall and extreme? Yeah...so far...but Google a bit about the Anasazi Indian culture and how it is so easy for conditions to swamp an entire culture...kind of a microcosm to comtemplate.